Pregnancy while on herceptin

[Rozebud]

I know someone who was dx'd stage IV and is currently NED and on herceptin. She thinks she *might* be pregnant. If so, anyone in the same situation that could comment? I know Stephanie Spielman discovered a second recurrance while pregnant and on herceptin and the baby is fine. Another survivor also had a baby that is fine while on hercepin (although premature labor). This was not planned, and it might not even be a pregnancy (still a couple days too early to test) but she is anxious and wants to gather information. Thanks!

[Becky]

Theorectically, one shouldn't get pregnant on Herceptin because the Her2 protein is needed for growth and cell reproduction and healing. Growth and cell reproduction are crucial in the developing embryo/fetus. However, obviously, your friends were fine but even Genentech does not recommend this as it could be a huge problem.


It is nice to see you post again. When I first joined in Oct or Nov 04 (just says Sept because Joe put up the new site and some of us had to rejoin - me included). I remember you being on alot then. I hope you are doing well.

[Rozebud]

Hey Becky - Good to see you too! Yes, I've been gone from this board for quite some time. I check in every month or too, saw Lisa's passing , but can't keep up. I"m on the YSC site every day, it's become my crack addiction .

I'm doing very well. 3 years this month! I can't help but believe that my odds have gone from crappy to great, all because of herceptin. How are you?

[Lani]

GROWTH FACTOR PATHWAY BLOCKING AGENTS
New anticancer therapies including small molecules and antibodies that block growth factor pathways are now in clinical trials and have shown considerable promise in combination with standard therapies in limiting the growth of some cancers. Examples of such drugs are herceptin, a blocking antibody to the Her-2/neu growth factor receptor, Iressa (ZD1839), a small molecule that prevents phosphorylation and activation of the epidermal growth factor receptor, and C225, a blocking antibody against epidermal growth factor receptor. In mouse xenograft models, C225 significantly inhibited tumor growth in combination with doxorubicin, but had only a modest effect alone. 42 C225 is now in clinical trials. Herceptin has already shown promise in a phase III trial in combination with first-line chemotherapy, 43 and has gained Food and Drug Administration approval in combination with other chemotherapeutic agents for the treatment of advanced breast cancer. Interestingly, the manufacturer has assigned a pregnancy risk category of B to herceptin based on extensive trials in monkeys without apparent fetal harm. Placental transfer in monkeys was demonstrated. No information is yet available about the effects of herceptin in human pregnancy; however, as the Her-2/neu pathway is critical to fetal development, the possibility of fetal damage in humans has not been excluded. At this time, the author recommends that management of cancer in pregnancy should limit the use of growth factor pathway blockers until more information is available. However, the possibility also exists, as suggested by the animal data, that such agents may result in a more favorable outcome in pregnancy for mother and fetus compared with standard chemotherapy. Additional information on the effects of such agents in pregnancy is clearly needed.

[Lani]

Obstet Gynecol. 2005 Mar;105(3):642-3. Links
Herceptin (trastuzumab) therapy during pregnancy: association with reversible anhydramnios.

Watson WJ.
Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, Mayo Clinic, Rochester, Minnesota 55905, USA. Watson.William@mayo.edu
BACKGROUND: Herceptin (trastuzumab), a new a chemotherapeutic agent, is a monoclonal antibody that blocks the human epidermal growth factor receptor 2 protein. There is no reported experience with use of this agent during pregnancy and possible effects on the fetus. CASE: A patient with breast cancer was treated with Herceptin during pregnancy. This treatment was associated with anhydramnios, which resolved slowly after the drug was discontinued. CONCLUSION: Although listed as a category B drug, experience with Herceptin in human pregnancy is limited, and it should be used with caution. Investigation of the role of human epidermal growth factor receptor 2 protein in the embryonic kidney may further our understanding of amniotic fluid dynamics.

[Lani]

1: Clin Breast Cancer. 2005 Oct;6(4):354-6. Links
Treatment of metastatic breast cancer with trastuzumab and vinorelbine during pregnancy.

Fanale MA,
Uyei AR,
Theriault RL,
Adam K,
Thompson RA.
Department of Lymphoma and Myeloma, The University of Texas M. D. Anderson Cancer Center, Houston, TX 77030, USA. mfanale@mdanderson.org
The management of breast cancer during pregnancy is a crucial clinical issue. It is important to evaluate the impact of chemotherapy on a woman and her fetus. Studies from our institution have demonstrated the safety and efficacy of treating women with adjuvant 5-fluorouracil/doxorubicin/cyclophosphamide during the second or third trimester of pregnancy. However, the literature regarding the treatment of metastatic breast cancer in a pregnant patient is scarce. In this article, we describe the successful treatment of a woman at 27 weeks of pregnancy with recurrent HER2/neu-overexpressing breast cancer who was symptomatic from multiple liver metastases. Per our review of the literature and to our knowledge, she is the first patient to be treated with weekly vinorelbine plus trastuzumab. Our patient had near complete resolution of her disease and delivered a healthy male infant at 34 weeks of gestation.

[Lani]

More

http://www.jco.org/cgi/content/full/24/2/321

[Rozebud]

Thanks Lani and Becky. She has been reading this post and appreciates the info !